The invention relates to power supply mechanisms for facsimile machines, and more specifically, to a power supply apparatus for a facsimile machine.
Most facsimile machines have two modes of operation: a main operating mode and a standby mode. In the main operating mode, power is supplied to the facsimile machine by a main power supply for performing all functions, such as transmitting facsimiles and receiving and printing facsimiles and confirmation reports. Many facsimile machines also perform other functions in the main operating mode, such as copying or scanning documents.
Most facsimile machines include a microprocessor-based controller that monitors various inputs and controls the overall operation of the facsimile machine. The controller also controls when the facsimile machine transitions between the main operating mode and the standby mode. Typically, after the facsimile machine has remained idle for a specified period of time, the controller causes the facsimile machine to transition from the main operating mode to the standby mode.
In the standby mode, the main power supply is de-energized to conserve power and to extend the life of various parts and equipment in the facsimile machine. A standby power source provides power to the controller, which must continue processing inputs and determine when to transition to the main operating mode.
Various types of standby power sources are used depending upon the requirements of a particular application. Some facsimile machines use a second, smaller power supply for standby mode that consumes less power than the main power supply. Other facsimile machines use a battery-based standby power supply. The primary disadvantages of this approach are that the batteries tend to be relatively heavy, are bulky and require a lot of space and also carry the risk that corrosive chemicals may leak from the batteries. Furthermore, both approaches require at least several watts to provide power to the microprocessor-based controllers used in most facsimile machines.
Based on the need for facsimile machines to operate in a standby mode to conserve power and the limitations in the prior approaches, a power supply apparatus for a facsimile machine that does not suffer from limitations of prior approaches is highly desirable. In particular, a power supply apparatus for a facsimile machine that provides standby power for a facsimile machine while avoiding the use of conventional batteries is desirable. A power supply apparatus for a facsimile machine that provides standby power for a facsimile machine while avoiding the use of a conventional standby controller is also desirable.
According to one aspect of the invention, a power supply switching apparatus for a facsimile machine is provided. The power supply switching apparatus comprises a power supply switch configured to selectively couple and decouple a power supply to the facsimile machine, a switch controller communicatively coupled to the power supply switch and being configured to control the power supply switch in response to the satisfaction of one or more switch criteria and a capacitor-based power supply communicatively coupled to the power supply switch and configured to provide power to the power supply switch.
According to another aspect of the invention, a power supply switching apparatus for a facsimile machine is provided. The power supply switching apparatus includes a power supply switch configured to selectively couple and decouple a power supply to a facsimile machine, a switch trigger communicatively coupled to the power supply switch and being configured to control the power supply switch in response to the satisfaction of one or more trigger criteria and a second power supply communicatively coupled to the power supply switch for providing power to the power supply switch.
According to another aspect of the invention, a facsimile machine is provided that comprises a main power supply and a capacitor-based power supply. The main power supply is configured to provide power for the facsimile machine when the facsimile machine is operating in a normal mode. The capacitor-based power supply is configured to provide power for the facsimile machine when the facsimile machine is operating in a standby mode